Fluid filter system



May 18, 1954 H. SPODIG FLUID FILTER SYSTEM 2 Sheets-Sheet 1 Filed May 8, 1950 KB 00 1 E 1 V 4 m KW m E H May 18, 1954 H. SPODIG FLUID FILTER SYSTEM 2 Sheets-Sheet 2 Filed May 8, 1950 Patented May 18, 1954 UNITED STATES PATENT OFFICE Claims priority, application Germany May 12, 1949 3 Claims.

This invention relates generally to fiuid filter systems and more particularly relates to a combined mechanical and magnetic filter system suitable, for example, for the oil sump or oil pan of an internal combustion engine.

Various types of mechanically operating oil filters are well known. These filters will remove relatively coarse particles of dirt or other impurities such as particles of cloth, wood fibers, carbonized oil, as well as larger metallic abrasions. However, such filters will not remove fine iron abrasions which may be of microscopic size. Such fine metallic abrasions will cause wear of the machine to be lubricated and ageing of the oil due to their catalytic effect.

Filters of the permanent magnetic type are also known. They are used to remove ferromagnetic particles from circulating oil. It has, for example, been suggested to provide the oil drain screw or an internal combustion engine with a built-in magnetic core to clean the oil. Such magnetic filters may be disposed in the gear case of an engine or in the oil sump or oil pan to remove ferromagnetic particles from the oil flowing past the filter. Such magnetic oil-drain screws have been found quite effective. However, in view of their small size they can accommodate only a small amount of abrasions; they will attract only those ferromagnetic particles which are contained in the oil that happens to flow past the magnetic oil drain screw.

It is also known to provide permanent magnet filter systems through which the fluid to be cleaned. is forced to flow. Such filter systems are provided outside of the engine in the pressure oil conduit. However. such filter systems through which a fluid i forced, are usually of complicated construction and hence expensive to manufacture. Furthermore, they suffer from the disadvantage that they cause a drop of the fluid pressure flowing therethrough when they are clo ed, up with, impurities.

It accordin ly object of the present inention to provide a novel combined mechanical nd magnetic filter system suitable, for Xample, or the oil circulating in an internal combustion en ine and which will overcome one or more of the disadvantages of prior art filters.

Another cbiect of the invention is to provide a combined filter of the character described which ma be disposed in the oil sump for the oil pump o on internal combustion engine.

A. further obiect of the invention is to provide a ter system for the oil circulating through an en ne which is of simple and inexpensive cons ruction and which may easily be removed for th purpose of cleanin it.

Tn accordance with the present invention there n provided a. combined mechanical and permanent magnet filter system particularly adapted for internal combustion engines which is arranged in the oil sump of the oil pan of the motor housing and within the suction region of the oil pump suction pipe. The filter is arranged in such a manner that the permanent magnet system simultaneously forms the oil sump into which extends the suction pipe of the oil pump.

The invention will be more readily understood as the description proceeds, taken in connection with the accompanying drawings, in which:

Fig. l is a sectional view of a conventional mechanical oil filter;

Fig. 2 is a sectional view of an oil filter system embodying the present invention;

Figs. 3 and l are sectional views of modified filter systems in accordance with the invention; and

Figs. 5 and 6 are a sectional view and a crosssectional view. respectively, of a further modification of the filter system in accordance with the invention.

Reference now to the drawings, in which like parts are designated by the same reference numerals, and particularly to Fig. 1, there is illustrated a mechanical oil sump filter system. The filter system is particularly adapted for internal combustion engines having forced oil circulation by means of an oil pump which may be a gear pump or a membrane pump. By means of the oil pump the oil is sucked from the lowest portion of the oil pan I through suction pipe 3. The oil pan I is arranged as an oil sump which collects the oil. The oil is then forced to the various portions of the engine to be lubricated including the hearing. In order to protect the engine from wear and to prevent the circulating oil conduits from clogging up a mechanicallv acting screen is provided into which the suction pipe 3 extends. The screen 2 is shown schematically in Fig. l and serves the purpose to remove coarser antimagnetic or diamagnetic particles as well as coarser magnetic or ferromagnetic particles.

In accordance with the present invention fine iron abrasions which may have microscopic size, and which will readily pass through screen 2 are also removed. To this end a permanent magnet filter system is provided within the eifective range of the oil suction pipe of the oil pump and within the oil sump. Such an arrangement is shown in 2. The magnetic filter may be disposed within screen 2.

As illustrated in Fig. 2 an annular magnet 5 is disposed within screen 2 and may consist particularly of aluminum-nickel alloys capable of bein hardened or of Alnico magnetic steel. Annular magnet 5 is disposed between two pole discs 5 of soft iron which therefore will conduct the magnetic lines of force. The magnetic lines of force N (north pole) and S (south pole) of the magnet 5 flow through the soft magnetic together with the bottom pole discs 6 so that a magnetic field of force N S is developed along the periphery of the pole discs t and within the air gap formed therebetween. The pole discs 4 which are in operative contact with the poles of the annular magnet 5 and are provided with a central aperture to receive pipe 3. Suction pipe 3 extends through screen 2 and pole discs 4. The magnetic system is supported by spacer rings 6 in the interior of screen 2 and may be secured to the oil sum l in any suitablemanner, for example, by screw or rivets as shown in Fig. 2. Oil sump l of the oil pan may have the shape of a flange as shown in Fig. 2 or it may be screwed into the oil pan so that the entire filter system may be removed for the purpose of cleansin it. The latter construction is shown, by way of example, in Figs. 3, 4, and 5.

Annular magnet 5 may have a circular, clliptical, rectangular cross-section or any other desired shape; it may also be subdivided into individual segments. The pole discs 4 may also be of circular, elliptical, rectangular or other shape.

The mechanically acting filter member 2 may be arranged as a late filter which may consist of felt plates or as a filter having gaps or bafiles or any other suitable mechanical filter may be used instead. In accordance with the invention screen 2, magnetic system 4, 5 and removable oil sump i of the oil pan form a complete filter system.

It is also feasible to arrange several magnetic systems of the type described in cascade within screen member 2. The oil circulates as follows. The oil contained in the oil pan flows through screen 2 and along the magnetic field of force N S of the magnetic system into the oil sump i where the antimagnetic or diamagnetic and the magnetizable impurities are removed. Then the oil is sucked through the oil suction pipe 3 of the oil pump and forced through the pressure con duits to the places to be lubricated.

Fig. 3 shows the same permanent magnet filter system including screen body 2, magnetic system 4, 5 and demountable or removable oil sump I. However, the screen body 2 is surrounded by a cover 7 which is open at the bottom and closed otherwise. As shown in Fig. 3 the oil sump l is arranged as a screw which may be screwed into the oil pan so that the filter system may easily be removed.

The oil circulates as shown by the arrows of Fig. 3. Thus the oil first rises between cover "I and screen 2, then enters the interior of the system through screen 2. Thereafter, the oil flows along the magnetic field of force N S of the magnetic system into the oil sump I wherefrom the cleaned oil is sucked through suction pipe 3.

Fig. 4 shows a modified sump filter system in accordance with the invention. The demountable part 5 of the oil pan is again arranged as a screw which is hollow. An annular magnet 5 having poles N and S is disposed in the hollow space within the screw which consists of iron. Hence the magnetic lines of force from the S pole of magnet 5 flow through screw l which conducts the lines of force, to form the S pole of the screw 5. Consequently, a magnetic field of force is developed between the S pole of screw l and the N pole of the annular magnet 5. The space within magnet 5 forms the oil sump of screw l. Screen 2,

and suction ipe 3 may be arranged in the same iii) 4 manner as described and shown in connection with Figs. 2 and 3. Again a permanent magnet sump filter system is formed.

Figs. 5 and 6 illustrate another sump filter system in accordance with the invention. In this construction, however, the magnetic system is disposed outside of the screen 2. Between the pole discs 4 of the magnetic system are arranged magnetic segments 5 having poles N and S, so that the circulating oil of the oil pan is permitted to flow through these spaces and through screen 2 into the oil sump which is arranged as a screw. The pole disc 4 and the magnetic segments 5 are connected by bolts 6 screwed into the bottom I.

In this case the magnetic system consists of 3 individual magnet arrangements as shown in Fig. 6. However, it is feasible to provide a larger or smaller number of such individual magnet arrangements.

The magnet segments 5 are disposed between the soft magnetic pole discs 4 of the system in such a manner that two S or two N poles of adjacent segments 5 rest against one of the pole discs 4. Consequently, reinforced magnetic N and S poles are developed at the periphery of the soft magnetic pole discs 4 and reinforced magnetic fields of force are hence developed in the space between the pole discs 4.

The sump filter system of the invention may be cleaned by removal of the demountable screw I of the oil pan with its magnetic system and screen member as a single unit. The filter may then be washed in gasoline or benzine, and the filtered impurities may be removed by means of compressed air. The other filter system disclosed herein are cleaned in a similar manner.

The invention has been described with reference to a preferred embodiment and it will be understood that many variations and modifications thereof may be resorted to without departure from the scope of the invention as defined in the following claims.

I claim:

1. A magnetic oil cleaner comprising an oil carrying sump, a filter located on top of said sump, a suction pipe extending through said filter into said sump, a magnetic system located within the range of the reduced pressure created by said suction pipe and consisting of at least one annular permanent magnet surrounding the end of said suction pipe and at least two annular pole discs located in direct operation contact with the same pole of said permanent annular magnet and surrounding the end of said suction pipe, said pole discs extending beyond the circumference of the pole surfaces of said permanent magnet, said filter being spaced from said pole discs to provide an annular magnetic field inside of said filter covered sump.

2. In a magnetic oil cleaner according to claim 1, a cover surrounding the filter and open on its lower end to force the oil to be cleaned upwardly along said filter.

3. A magnetic oil cleaner according to claim 1 and means to connect the same with a detachable part of the oil sump.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,149,764 Frei Mar. '7, 1939 2,307,954 Radke Jan. 12, 1943 

